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991.
In the United States, Congress has had a long-standing interest in consumer privacy and the extent to which company practices are based on fair information practices. Previously, public policy was largely informed by anecdotal evidence about the effectiveness of industry self-regulatory programs. However, the Internet has made it possible to unobtrusively sample web sites and their privacy disclosures in a way that is not feasible in the offline world. Beginning in 1998, the Federal Trade Commission relied upon a series of three surveys of web sites to assess whether organizations post online privacy disclosures and whether these disclosures represent the U.S. definition of fair information practices. While each year's survey has provided an important snapshot of U.S. web-site practices, there has been no longitudinal analysis of the multiyear trends. This study compares a subset of equivalent individual-level web-site data for the 1998, 1999, 2000, and 2001 web surveys. Implications for using this type of research to inform public policy are discussed. 相似文献
992.
Serum free fatty acids (FFA) in 100 parturient (50 primiparous and 50 multiparous volunteers) and 50 female patient (30 patients 20–30 years age group and 20 patients 31–50 yrs age group) volunteers undergoing elective major abdominal surgery were monitored during different stages of delivery and surgery respectively. FFA increased in both primiparous and multiparous from full term (46 mg%) to second stage of labour (60 mg%) and gradually decreased to 38 mg% on the third day postpartum. The intergroup comparison between primiparous and multiparous was significant. Surgical stress also increased FFA from the day of admission (21 mg%) to the preoperative stage (35 mg%). The intergroup comparison between 20–30 yrs age group and 31–50 yrs age group did not show any significant change. 相似文献
993.
Nomographs for determining the filter order of classical filters based on selectivity requirements are presented. The selectivities for a variety of standard classical filters are summarized in equation form and the general selectivity nomograph is constructed. The selectivity equations are then converted into nomograph form by applying the relationship between the transfer function and the response slope. Design examples are presented to demonstrate the usefulness of the selectivity nomographs. These nomographs can be used to gauge filter performance and combined with optimization techniques can yield superior classical filter designs. 相似文献
994.
A study is made of the orthogonal polynomials on certain curves in the complex plane. Necessary and sufficient conditions for a set of polynomials to be orthogonal on the curves are obtained in terms of symmetric matrices. The relations of the symmetric matrices to Toeplitz matrices and innerwise matrices are shown. 相似文献
995.
The purpose of this study was to examine which emergent literacy skills contribute to preschool children's emergent writing (name-writing, letter-writing, and spelling) skills. Emergent reading and writing tasks were administered to 296 preschool children aged 4-5 years. Print knowledge and letter-writing skills made positive contributions to name writing; whereas alphabet knowledge, print knowledge, and name writing made positive contributions to letter writing. Both name-writing and letter-writing skills made significant contributions to the prediction of spelling after controlling for age, parental education, print knowledge, phonological awareness, and letter-name and letter-sound knowledge; however, only letter-writing abilities made a significant unique contribution to the prediction of spelling when both letter-writing and name-writing skills were considered together. Name writing reflects knowledge of some letters rather than a broader knowledge of letters that may be needed to support early spelling. Children's letter-writing skills may be a better indicator of children's emergent literacy and developing spelling skills than are their name-writing skills at the end of the preschool year. Spelling is a developmentally complex skill beginning in preschool and includes letter writing and blending skills, print knowledge, and letter-name and letter-sound knowledge. 相似文献
996.
This study documents the reliability and validity of a new infant-toddler authentic assessment, the Learning Through Relating Child Assets Record (LTR-CAR), and its feasibility of use by infant-toddler caregivers in an Early Head Start program. In a sample of 136 children, results indicated a strong internal structure of the LTR-CAR as evidenced by high internal consistency within age bands, expected performance in terms of the order of difficulty of items, and expected performance relative to the chronological ages of children. Moreover, the LTR-CAR accounted for a statistically significant amount of unique variance (between 6 and 26%), over and above age and gender, in six out of eight regressions predicting criterion measures. Given the increasing numbers of infants and toddlers in non-parental care, the need for authentic assessment as a tool to plan meaningful learning opportunities, as well as the lack of evidence-based authentic assessment options at the infant-toddler level, the LTR-CAR may provide a viable option for the field. 相似文献
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V. S. Sunder 《Resonance》2011,16(2):165-179
In this homage to the late I M Gelfand, we try to give an overview of some of his contributions to the theories of Banach
algebras in general and C*-algebras in particular, and briefly elaborate on the celebrated Gelfand-Naimark-Segal construction which gives a way of
passing from positivity-preserving linear functionals to representations on Hilbert space. 相似文献